JPS6193411A - Connecting method of optical fiber in composite transmission line consisting of optical fiber - Google Patents

Abstract

PURPOSE:To make usable a composite optical fiber for at least one of plural transmission lines by providing a connecting box for optical fibers to the jumper fittings of a tension resistant steel tower part, introducing the terminals of the optical fiber into the connecting box and connecting the optical fibers. CONSTITUTION:The transmission lines 2 (at least one of which is the composite optical fiber) are anchored to the steel tower 1 by insulator devices 4. Plural pieces of jumper wires 9 for transmission connecting right and left anchor clamps 3 are supported to an annular frame 8 supported by the jumper fittings 7 supported by yoke materials 6 of the insulator devices via suspending materials 5 to the side part of the tower 1. The connecting box 10 for the optical fibers is provided to the jumper fittings 7 and the terminals of the optical fibers 11 led out of the anchor ends of the composite optical fiber wires are introduced into the box 10 and are connected to each other. Since there is no need for conducting the optical fibers to the steel tower, the insulating characteristic to the steel tower can be assured by the insulator device between the wire ends and steel tower and since the connecting box is enclosed by the plural jumper wires, corona discharge is prevented as well.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for connecting optical fibers in a tension tower anchoring portion of an optical fiber composite power transmission line.

[Conventional technology and its problems]

Conventionally, there have been various studies on incorporating optical fibers into overhead power transmission lines. However, in the case of optical fiber overhead ground wires that are already in practical use, the terminal of the optical fiber pulled out from the ground wire can be placed in a junction box installed on a steel tower, but the optical fiber pulled out from a power transmission line can be connected to a junction box on a steel tower. When introduced, the optical fiber becomes a dielectric and causes corona discharge.

In particular, this poses extremely difficult problems in terms of ensuring insulation.

This is a factor that hinders the use of optical fiber composite power transmission lines (
7) It is one.

However, in some foreign countries, power transmission lines without an overhead ground wire are permitted, and such power transmission lines are necessarily required to incorporate optical fibers into the transmission line. too.

There may be cases where it is advantageous to incorporate optical fibers into power transmission lines. Therefore, it can be said that establishing a technology for connecting optical fibers in optical fiber composite power transmission lines is an essential issue in this industry.

This invention was made for the purpose of solving the above problem.

[Means for solving problems]

A method of the present invention for achieving the above object includes providing an optical fiber junction box in a jumper fitting of a tension tower section that supports a plurality of jumper wires at fixed points on the outer periphery.

It is characterized in that the terminal of the optical fiber pulled out from the holding end of the power transmission line is introduced into this connection box and connected. According to this method, there is no need to guide the optical fiber to the steel tower, so insulation between the wire and the tower can be ensured by an insulator device between the wire end and the steel tower. Since it is located inside surrounded by , it can also prevent sycorona discharge for the reason described later.

〔Example〕

Embodiments of the method of the present invention will be described below with reference to the accompanying drawings.

Reference numeral 1 in Figure 1 is a steel tower, with tensioned transmission lines 2, (
This line (actually a plurality of lines, at least one of which is a composite optical fiber line) is anchored to the tower via an insulator device 4 that supports a tie clamp 3. Further, a jumper metal fitting 7 is provided on the side of the steel tower and is supported by a yoke material 6 of the insulator device via a hanging member 5, and the left and right retaining clamps 3°3 are connected to the annular frame 8 supported by this metal fitting. A plurality of jumper wires 9 for power transmission are supported at regular intervals in the circumferential direction.

The optical fiber connection work according to the invention of 1 or more is similar to that of a general anchoring section, in which an optical fiber junction box 10 is installed on the jumper fitting 7 of the tension tower section, and the optical fiber connection box 10 is The optical fiber 11 (shown by the dotted line in the figure is drawn out through the clamp 3) drawn out from the retaining end of the fiber composite electric wire is placed along the jumper wire of the transmission line until the connection box is installed. After guiding, the ends of the fibers are introduced into junction box 10 and interconnected to complete.

The junction box used in this case includes a main body 13 having a plurality of fiber introduction ports 12, as shown in FIGS. 2 and 3.
If a method is adopted in which a box made of cast aluminum or the like and consisting of a lid 14 that seals the fiber connection part is brought into close contact with the outer surface of the jumper fitting 7 and fixed with a fastening member such as a stainless steel band 15, installation to the existing jumper fitting is adopted. is possible. However, the method is not limited to this. For example, the junction box may be housed inside the jumper fitting.

The jumper fitting and the connection box may be formed integrally from the beginning. Note that the shape of the connection box can be arbitrarily determined according to the shape of the jumper fitting.

Note that when optical fibers are combined into power transmission lines, the outer periphery of the fibers is often covered with a metal tube such as an aluminum pipe to protect the fibers. In this case, it is desirable to also lead the protective metal jacket to the junction box to protect the optical fiber pulled out from the clamping end of the wire, but this jacket serves as a conductive path and current flows to the junction box. is not desirable. Therefore, in such a case, as shown in FIG. 4, electrical insulation is provided at at least one place by interposing an insulating material 17 between the junction box 10 and the metal jacket 16 introduced therein. It is desirable to prevent current from flowing to unnecessary locations.

〔effect〕

As described above, when optical fibers are connected within a junction box attached to or integrated with a jumper fitting, insulation from the steel tower can be ensured. Also.

There are multiple jumper wires with low electrical resistance around the junction box, and current flows through the wires, and a potential difference is created between the junction box and the optical fiber, as when the junction box is installed on a steel tower. For two reasons, the flow of current through the optical fiber and the resulting corona discharge are also prevented. Therefore, according to the present invention, it becomes possible to use a composite optical fiber line for at least one of the plurality of power transmission lines, increasing the degree of freedom in designing a power transmission line equipped with an optical communication line.

[Brief explanation of drawings]

Fig. 1 is a front view of a tension tower section in which optical fibers are connected by the method of the present invention, Fig. 2 is a front view showing an example of how an optical fiber connection box is installed, and Fig. 3 is a side view thereof. , FIG. 4 is a sectional view showing an example of insulation between a junction box and an optical fiber replacement jacket. DESCRIPTION OF SYMBOLS 1... Steel tower, 2... Power transmission line, 4... Insulator device, 5... Hanging material, 7... Jumper metal fittings, 9... Jumper wire. 10... Junction box, 11... Optical fiber, 12...
Introduction port. 13...Body, 14...Lid, 15...Band, 1
6...External waves, 17...Insulating material patent applicant: Sumitomo Electric Industries, Ltd. Agent: Kama 1) Text: double digits, 1 figure, value 2 figure

Claims (2)

[Claims] (1) In the tension tower section of an overhead power transmission line, an optical fiber junction box is fixed on the surface of the jumper metal fitting that supports multiple jumper wires at fixed points on the outer periphery, or is integrated with the metal metal fitting or the metal fitting. 1. A method for connecting optical fibers in an optical fiber composite power transmission line, characterized in that the terminal portion of the optical fiber pulled out from the retaining end of the power transmission line is introduced into the connection box and connected. (2) The protective metal jacket of the optical fiber mentioned above is also pulled out from the retaining end of the power transmission line together with the optical fiber, and its terminal part is introduced into the junction box through the insulating material, and the optical fiber pulled out from this introduced end is A method for connecting optical fibers in an optical fiber composite power transmission line according to claim 1, wherein the connection is performed within a junction box.